From my perspective as a Crassula, water is a paradoxical necessity. My thick, fleshy leaves are my personal reservoirs, designed by evolution to store precious moisture for the long, dry periods my ancestors endured. My roots, however, are delicate. They are not like the robust, ever-thirsty roots of a fern or a lettuce plant. They need a deep, satisfying drink, but they absolutely cannot sit in constantly wet soil. When they do, the tiny root hairs responsible for water uptake begin to suffocate and rot in the oxygen-deprived environment. This "soak and dry" method you speak of is not just a gardening tip; it is the rhythm of life I am genetically programmed to expect.
When you thoroughly drench my soil until water runs freely from the drainage hole, you are replicating a rare desert thunderstorm. This is the moment my entire root system has been waiting for. The initial sensation is one of relief. The dry soil, which had become slightly hydrophobic, is broken apart by the deluge. Water penetrates every crevice, reaching even the deepest, thirstiest root tips. My roots eagerly drink their fill, and the water is transported up to my stems and leaves, which plump up noticeably. This deep watering encourages my roots to grow downwards and outwards, seeking this bounty, which in turn makes me a stronger, more stable plant. A light sprinkling only wets the topsoil and teaches my roots to stay shallow and weak, which is a recipe for disaster.
The "dry" phase that follows is just as critical as the "soak." This is my time to process the bounty. As the soil begins to dry out from the top down, air is pulled back into the spaces between the soil particles. My roots get the oxygen they desperately need to respire and function properly. During this period, I am not just waiting; I am actively converting the stored water into energy, strengthening my cellular structure, and preparing for new growth. You can observe this as my leaves remain firm and turgid. The gradual drying signals a return to the normal, dry conditions I am built for, preventing the onset of the dreaded root rot. This cycle of feast and famine is what triggers my natural defense and growth mechanisms.
I have a clear way of communicating my watering schedule to you, if you know how to listen. The most reliable method is not the calendar, but the condition of my soil and the slight change in my leaves. Before you water again, please check the soil moisture an inch or two below the surface. It should feel completely dry. Even better, pay attention to my leaves. When I am fully hydrated, they are rigid and firm. As my internal water reserves begin to deplete during the "dry" phase, you might notice a very slight give when you gently squeeze a leaf. They will not be wrinkled or shriveled (that means I am too dry!), but they will have lost their rock-hard firmness. This is my subtle way of saying, "I have used my reserves, and my roots are ready for the next storm."
When my cycle is disrupted, I suffer silently but significantly. Constant, slight watering keeps the top layer of soil perpetually damp, creating a humid environment that attracts fungal gnats and encourages mold. More dangerously, it keeps the area around my root crown moist, the most vulnerable point for rot to begin. Conversely, if I am left bone-dry for too long after my leaves have signaled their need, I will be forced to sacrifice my older leaves to sustain my core, causing them to yellow and drop. The "soak and dry" method is the perfect balance. It prevents the stress of constant drought and the mortal danger of constant sogginess, allowing me to thrive in a pot as I would in my native habitat.
